Tape winding machine

ABSTRACT

The provision winding machine for tape includes a takeup spindle on which the tape from a letoff source is wound, a reciprocating traverse guide having sidewalls for guiding the tape in passing to the takeup spindle, a tape guide bar movably positioned in the tape path leading from the letoff source, and means for altering the relative positions between the tape guide bar and the takeup spindle during winding to assist the tape to move with the traverse guide away from its natural straight line path on the outward strokes, and to retard the movement of the tape back towards the natural straight line path on the return strokes, thereby preventing the tape from being crushed against the sidewalls of the traverse guide.

United States Patent [72] Inventor John Kay Irllgle Mattie Belfast,Northern Ireland [21] Appl. No. 772,088 [22] Filed Oct. 31,1968 [45]Patented Aug. 10, 1971 [73] Assignee Janet Medtle a Sons Limited lellut,Northern Ireland 32 Priority Nev.2,1967 [33] Great Britain a 11 9818/67[54] TAPE WINDING MACHINE 7 Claims, 4 Drawing Ilge.

[52] 11.8. CI. 242/158 11, 242/67.l R [51] lot. CL 5651: 54/28 [50]I'IeldolSeareh 242/158, 158.1,158.2,158.3,158.4, 55,67.1,43,61,62, 76,BIG. 2; 139/304, 306

[56] ltelereneeecled UNITED STATES PATENTS 774.323 1 H1904 Ilene 139/306868,268 10/ 1907 Holmes et a1 139/306 1,267,080 5/1918 .Iudelshon242/67.1

Weiss 242/671 1,867,596 7/1932 Roseman.... 242/158.3 X

2,135,668 1 1/ 1938 .Iudelshon 242/67.l X

2,220,613 1 III 940 Parkes et al. '242/76 X 2,476,070 7/ 1949 Solliday242/76 X 2,782,029 2/1957 Uritis........... 242/76 2,989,265 6/ 1 961Selsted 242/76 FOREIGN PATENTS 426,449 4/ 1935 Great Britain 242/55 1964,062 4/ 1967 Great Britain 242/55 Primary Examiner-Stanely N.Gilreath Att0mey--DovveI1& Dowell ABSTRACT: The provision windingmachine for tape ineludes a takeup spindle on which the tape from aletofi source is wound, a reciprocating traverse guide having sidewallsfor guiding the tape in passing to the takeup spindle, a tape guide barmovably positioned in the tape path leading from the letofl eource, andmeans for altering the relative positions between the tape guide bar andthe takeup spindle during winding to assist the tape to move with thetraverse guide away from its natural straight line path on the outwardstrokes, and to retard the movement of the tape back towards the naturalstraight line path on the return strokes, thereby preventing'the tapefrom being crushed against the sidewalls of the traverse guide.

PATENIEDmsiman I 3598,33?

sum-10m EL kt Inventor;

PATENTED AUG 1 0 an sum 3 or 4 TAPE WINDING MACHINE DESCRIPTION OFINVENTION This invention relates to textile winding machines and isparticularly concerned with precision winders for tapes of for examplepolypropylene.

When a tape of material such as polypropylene emerges from anextruder/stretch unit or other substantially fixed letoff source ittends to move in a straight line from the source. However if the tape isto be wound directly from the letoffinto a package it must he traversedalong the length of the package and it has been found that theresistance to movements of the tape away from the straight line pathcauses the edge of the tape to be crushed against the trailing edge ofthe traversing device during movement away from the letoff path to anextremity of the package. On the return movement from an end of thepackage to the letoff path the friction of the tape may resist thedesired movement again tending to cause the tape to be crushed againstthe traverser even though there is a natural tendency of the tape toresume its straight line path. However the resistance to movement duringthe return is less than that during movement away from the straight linepath.

In order to avoid, or diminish, the crushing of the tape, a precisionwinding machine for tape wherein the tape is laid on a takeup spindle bya reciprocating traverse guide has, in accordance with the invention, atape guide member (or members) positioned in the tape path between theletoff source and the takeup spindle, means being provided to alter therelative position of the tape guide and takeup spindle during winding.Thus the shape of the guide and its position relative to the spindle atany instant during traverse can be arranged to provide a relatively highdegree of bias on the tape in the direction to cause the tape morereadily to be moved by the traverse guide from the straight line pathleading from a source of supply to an end or extremity of the packagebeing wound and a lesser degree of bias or even a negative bias toretard the movement of the tape, on its travel from an extremity to thestraight line path.

Ideally the tape guide member should engage the tape prior to thetraverse guide as this allows the traverse guide to be maintained closeto the package but a significant decrease in crushing can be obtainedwith the guide positioned between the traverse guide and the takeuppackage. Further it is not essential that the tape guide be positionedin the preferred disposition to one side of the traverse guide in thetape path as it could be positioned above or below the traverse guide,the wings (or their equivalent) of the traverse guide being sufficientlylong to act on the tape.

While it is envisaged that the tape guide could be stationary and thespindle moved it is preferable for the tape guide to be moved oradjusted during winding in time with the movement of the traverser.

An example ofa movable guide member is a bar preferably of circularcross section, shaped as a shallow or wide angled V, the apex thereofpreferably being radiused so that both sides of the guide meet in asmooth curve. The bar is positioned approximately parallel with the axisof the spindle of the takeup package and at a lower level than thetraverse guide so as to influence the position of the tape within thetraverse guide. The bar is connected, preferably at one end, tomechanism which will automatically alter its position relative to thespindle in timed relationship with the movement of the traverse guide.When the tape is returning from one extremity of the passage, to thestraight line path which is for example at the midpoint of the package,that part of the bar which the tape engages may be substantiallystraight or slightly sloped towards the spindle to assist the return ofthe tape towards the middle of the package. The other half of the bar isat a greater slope as the bias will have to be greater to prevent thetape being crushed against the side of the traverse guide when the guideis moving the tape away from the midposition opposite the letoff. Onceit reaches the end of its traverse, however, the position of the bar iswell nigh instantaneously altered to cause the greater sloped part ofthe bar to become substantially horizontal because the tape will now bereturning towards the letoff path. The other part of the bar will thenbe at a greater slope because it has now to assist the traverse of thetape away from the letoff or straight line path.

It may be desirable in some instances, to be able to alter the positionor shape of the tape guide relatively to the spindle I during windingsince if for example the tape is polypropylene which is being suppliedby an extruder it might otherwise be necessary to have to stop theextruder to carry out a small adjustment to the tape guide needed forexample by the fact that tapes have different coefficients of friction.Such an adjustment can be allowed for by adjustably connection the twoarms of the V-shaped guide at the apex and then altering the anglebetween the two arms. In general however a guide having an includedangle of about l75 has been found to be suitable for most tapes. I

If the letoff point was positioned at one end of the package so that thestraight line path was also at one end then a straight bar need onlyhave its angle to the spindle altered once during each traverse cycle.However the more normal arrangement is to have the letoff pointpositioned at the midpoint of the package.

As a further alternative the guide member could comprise two wingsmounted on an axis substantially parallel with that of the spindle andpivoting back and forth in a radial direction to substitute one wing forthe other at the ends of the traverse movement, the wings, being shapedto give a different degree of bias during traverse from and to, thestraight line path.

It is most desirable for the position of the tape guide member to bealtered very quickly or else the bias provided by the member will tendto increase the tape crushing effect rather than to diminish oreliminate it. The means to cause the movement of the tape guide may forexample comprise a pneumatic or hydraulic pistonand cylinder actingdirectly on a pivoted tape guide and controlled by limit switchesactuated when the traverse guide reaches the two extremities of itstravel or at any other suitable points. However any other suitablearrangement can be used.

An embodiment of a precision winder for tape, in accordance with thisinvention will now be described by way of example with reference to theaccompanying sketch drawings in which:

FIG. 1 is a diagrammatic front view of the main working parts of thewinder;

FIG. 2 is a perspective view drawn at a slight angle to the front of thepackage; and

FIG. 3 is an end view of the drive gearing taken from the right-handside of FIG. 1.

FIG. 4 is a diagrammatic view of the fluid circuit.

Referring to the drawings, polypropylene tape 2 -is fed in a straightline path from an extruder (not shown) forming a letoff source, to thecenter point of a takeup spindle 4 and between the spindle and apressure roll 6. During its passage it passes beneath a tape guidemember in the form of a bar generally indicated at 8 and between thearms of a traverse guide I0.

The spindle 4 is driven during winding at a progressively reducing speedso as to compensate for the increasing diameter of the package [2 beingwound on the spindle. It is pivotally mounted on the machine by means(not shown) so as to move away from the pressure roll 6 as the packagediameter increases.

The tape guide member 8 which is pivoted at 14 to a support bracket 16forming part of the frame (and not shown in FIG. 3) comprises two arms18 and I8 connected together to form a shallow V.

The traverse guide 10 is mounted on a rod 20 connected by a bracket 2]to a nut 22 on a rotating traverse screw 24 which causes the traverseguide to be reciprocated along the length of the takeup package 12 onthe spindle 4.

The traverse screw is connected to the drive for the spindle 4 by achain 26 (see FIG. 3) which drives a chain wheel 28 rotatably mounted ona fixed shaft 30 and integrally connected to a gearwheel 32 which mesheswith a gear 34 mounted on a stub axle 36 mounted on a bracket 38. Thegear 34 meshes with a further gear 40 also mounted on the bracket 38.

The bracket 38 is pivotally mounted on the shaft 30 and is rockable by apneumatic piston and cylinder device generally shown at 42 between alower position in which the bracket 38 engages an adjustable stop 46 andin which the gear 34 engages a gear 454 carried on the end of thetraverse screw 24, the gear 40 not meshing therewith, and an upperposition in which the bracket engages a stop 48 and the gear 40 mesheswith the gear 44, the gear 34 being then out of mesh.

The nut 22 carries a U-bracket 50 which extends downwardly and straddlesthe fixed shaft 30. Each limb of the U-bracket carries a trip valve 52,53 in line respectively with two plates 54, 55 secured to the shaft 30.When the nut 22 and hence the traverse guide is moving from right toleft as seen in the drawing, the valve 52 will contact the upper plate54 to reverse the flow of fluid to the cylinder 42 which then acts topivot the bracket 38 and to thus cause the gear 34 to mesh with the gear44 reversing the drive to the gear 44 on the traverse screw 24. At theend of this traverse the valve 53 will strike the lower plate 55 againcausing the piston and cylinder 42 to act to reverse the drive to thescrew 24. The spacing of the plates 54, 55 thus determines the length oftraverse of the guide 10.

Operation of the trip valves 52, 53 also causes a cylinder 56 connectedto the tape guide 8, to be charged or discharged and hence the guide 8to assume its required position at the correct point in the traversecycle. The cylinder 56 is attached to the bracket 16 by a strap 58 andits piston 60 to one side of the guide 8. Adjustable stop screws 62 aremounted on the bracket 16 one on each side of the pivot 14 to preventthe guide pivoting beyond its required positions. FIG. 4 shows a fluidcircuit diagram containing the fluid cylinders 42 and 56, also thevalves 52 and 53, and their associated stops 54 and 55, for rocking thearm 18 in the desired directions during the winding cycle.

The trip valves 52 and 53 are connected to a valve 62 via pilot pressurelines (shown dashed). When one of the valves 52 or 53 is operatedpressure is applied via the respective pilot pressure line to the valve62 which operates to reverse the pressure and drain connections to thecylinders 42 and 56. The valve 62 is a directional spool valve which hastwo positions determined by pilot pressure from one or other of thevalves 52 and 53. The dashed lines are not shown solid since they aresignal or pilot pressure lines rather than working lines.

When the tape is in the position shown in FIG. 2 it is being moved fromthe left-hand end of the package to the midpoint where it will lie on astraight line path from the extruder nozzle. Thus there is a tendencyfor the tape to move back to the midpoint and no additional bias needsto be provided by the tape guide. There is however a certain amount offrictional resistance to movement of the tape which tends to balance thenatural tendency of the tape to resume its straight line path and thusthe arm 18 of the guide 8 is shown in the drawings in full lines(FIG. 1) as being parallel to the spindle.

When the tape passes the midpoint and is being moved by the traverseguide towards the right-hand end ofthe package it is being deflectedfrom its straight line path and hence tends to resist its movement andthus to be crushed against the trailing arm of the traverse guide. Thisis counteracted by the fact that the arm 18' of the tape guide slopesupwardly towards the spindle so as to exert a bias on the tape whichpasses beneath the guide bar, to keep it properly positioned in thetraverse guide without crushing.

On the tape reaching the right-hand end of the package it is necessaryto pivot the tape guide so that the arm 18' is parallel tothe spindleand the arm 18 extendsupwardly towards the spindle. This pivotalmovement is achieved by means of the pneumatic cylinder 56 the piston 60of which is pivotally secured to the arm 18' of the tape guide. Thecylinder is pressurized by operation of the trip switch 53 and pivotsthe guide to the position shown in dot and dash lines in the drawings.

The tape now travels on its traverse from right to left over the arm 18'which is now parallel to the spindle and over the arm 18 which slopestowards the spindle until it reaches the left-hand end when the tripswitch 52 operates to reverse the cylinder 56 and move the guide 8 tothe position shown in full lines.

The winding machine can, if desired, be a multispindle machine in whichcase the settings of the guide member 8 for each spindle can be arrangedto give a different bias from its neighbor so as to accommodate aslightly different tape delivery point from the extruder stretch unitfor each tape, i.e., if there are four tapes side by side coming fromthe stretch unit the delivery position relative to the winding machinewill vary for each spindle according to the width of the tape. Ofcourse, the positions of the actual winding heads could be setaccordingly, but it is more simple to keep these in lines on the machineand vary the position which each guide member will assume for bothdirections of traverse.

lclaim:

l. A precision winding machine for tape comprising a takeup spindle onwhich the tape from a letoff source is wound a reciprocating traverseguide having sidewalls for guiding said tape in passing to the takeupspindle; a tape guide bar movably positioned in the tape path leadingfrom the letoff source; and means for altering the relative positionsbetween the tape guide bar and the takeup spindle during winding toassist the tape to move with the traverse guide away from its naturalstraight line path on the outward strokes, and to retard the movement ofthe tape back towards the said straight line path on the return strokes,thereby preventing the tape from being crushed against the sidewalls ofthe traverse guide.

2. A tape winding machine as claimed in claim I, in which the tape guidebar is positioned to engage the tape prior to its engagement by thetraverse guide.

3. A tape winding machine as claimed in claim 1 in which the tape guidebar has the shape of a wide-angled V.

4. A tape winding machine as claimed in claim 3 in which the tape guidebar is of circular cross section, and is pivoted to the machineframework adjacent the apex of the V.

5. A tape winding machine as claimed in claim A wherein the bar isarranged so that when one arm of the V is parallel to the axis of thetakeup spindle the other arm slops towards the spindle.

6. A tape winding machine as claimed in claim 1 in which the traverseguide is reciprocated by a pair of gears mounted on a pivoted plate, thegears being driven in opposite directions; and means to pivot the plateto position in which the gears alternately engage a corresponding gearon a screw driving the traverse guide.

7. A tape winding machine as claimed in claim 1 in which the means toalter the relative positions of the tape guide bar and the spindleoperates only when the traverse guide has reached either end of itsreciprocating motion; and in which the means for altering the relativepositions of the tape guide bar and takeup spindle comprises a fluidactuated piston and cylinder, and valve means associated with the drivefor the traverse guide to reverse the direction of movement of thepiston at each end of the traverse movement.

1. A precision winding machine for tape comprising a takeup spindle onwhich the tape from a letoff source is wound a reciprocating traverseguide having sidewalls for guiding said tape in passing to the takeupspindle; a tape guide bar movably positioned in the tape path leadingfrom the letoff source; and means for altering the relative positionsbetween the tape guide bar and the takeup spindle during winding toassist the tape to move with the traverse guide away from its naturalstraight line path on the outward strokes, and to retard the movement ofthe tape back towards the said straight line path on the return strokes,thereby preventing the tape from being crushed against the sidewalls ofthe traverse guide.
 2. A tape winding machiNe as claimed in claim 1, inwhich the tape guide bar is positioned to engage the tape prior to itsengagement by the traverse guide.
 3. A tape winding machine as claimedin claim 1 in which the tape guide bar has the shape of a wide-angled V.4. A tape winding machine as claimed in claim 3 in which the tape guidebar is of circular cross section, and is pivoted to the machineframework adjacent the apex of the V.
 5. A tape winding machine asclaimed in claim 4 wherein the bar is arranged so that when one arm ofthe V is parallel to the axis of the takeup spindle the other arm slopestowards the spindle.
 6. A tape winding machine as claimed in claim 1 inwhich the traverse guide is reciprocated by a pair of gears mounted on apivoted plate, the gears being driven in opposite directions; and meansto pivot the plate to position in which the gears alternately engage acorresponding gear on a screw driving the traverse guide.
 7. A tapewinding machine as claimed in claim 1 in which the means to alter therelative positions of the tape guide bar and the spindle operates onlywhen the traverse guide has reached either end of its reciprocatingmotion; and in which the means for altering the relative positions ofthe tape guide bar and takeup spindle comprises a fluid actuated pistonand cylinder, and valve means associated with the drive for the traverseguide to reverse the direction of movement of the piston at each end ofthe traverse movement.